Cavitation Erosion Resistance of TiSiN/NiTiAlCoCrN Nanomultilayer Films with Different Modulation Periods

Abstract

In order to explore the effect of modulation period on the structure and properties of TiSiN/NiTiAlCoCrN nanomultilayer films, the films were deposited on 304 stainless steel via a magnetron sputtering system. The structure and element distribution of the films were observed via X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The cavitation erosion of the films was investigated using an ultrasonic vibration cavitation machine. The results show that the TiSiN/NiTiAlCoCrN nanomultilayer film exhibits a face-centered cubic (FCC) structure and preferred orientation on the (200) crystal plane. TiSiN/NiTiAlCoCrN nanomultilayer films grow in the form of columnar crystals, which grow perpendicularly to the direction of the substrate. With increasing modulation periods, the hardness, elastic modulus, and adhesive force firstly increase and then decrease. When the modulation period is 11 nm, the TiSiN/NiTiAlCoCrN nanomultilayer film has the biggest hardness of (14.649 ± 0.591) GPa, elastic modulus of (249.065 ± 10.485) GPa, and adhesive force of 11.3 N. With increasing modulation periods, the mass loss firstly decreases and then increases. When the modulation period is 11 nm, the mass loss is the minimum of 0.6 mg. There are two reasons for improving the cavitation erosion resistance of the films. The TiSiN/NiTiAlCoCrN nanomultilayer film has the highest hardness, and the interfaces of the nanomultilayer film can hinder the generation and expansion of cavitation pits.